The usual way of handling a flying truss deck form is to lower it into position from above using a crane, and to support it in the selected pouring location by means of cribbing or multiple high capacity jacks, which jacks are usually made up of several component parts and are very limited in vertical range without changing components, whereby it is necessary to replace some of the component parts in order to change the height range. These supporting jacks are not usually fixed to the trusses of the deck form, but are handled as separate units which are removed from the truss deck form whenever it is being moved to a new location. Once a floor has been poured and cured on these deck forms, each form must have its weight transferred from the shore jacks to independent lowering jacks resembling garage-type hydraulic jacks, or crank operated lowering jacks, which are customarily used as separate equipment not only to support the deck forms from below while the supporting jacks under the trusses are being removed, but which are then used to lower the deck form to strip it from the cured concrete and to place it on multiple dollies, on which the deck form is rolled to the edge of the building and out therebeyond on form glide rollers to a partially extended position where the operation of rigging it to the crane commences. The jacking of the deck form between the dolly level and the pouring level, first to raise it and later to lower it, is most time consuming. Moreover, in the past it has been necessary to remove the supporting jacks from beneath the trusses before they can be rolled on their lower chords over the form glides in order to extend the deck form beyond the building line and out from under the recently poured and cured floor.
The prior art shows various deck form handling and supporting means analagous to individual features of the present invention, but without teaching the combination of apparatus or steps required to achieve present purposes.
For instance, U.S. Pat. No. 3,787,020 to Avery shows small screw jacks attached to the lower beams of a flying truss deck form in such a way that they can be pivoted up above the truss bottoms. These jacks are of very limited range in their capability to change height. The patent shows a technique for moving the form by rolling it on the floor upon which it rests using clamped-on beam rollers which, however, lack steering capability.
U.S. Pat. No. 3,744,945 to Metrailer shows a shallow-truss deck form using very long shore jacks which, however, can not be detached in such a way as to leave the lower truss chords free for rolling on a form glide, because the jacks are mounted on downwardly extending stubs welded to the lower surfaces of the truss beams. Metrailer uses a single carriage for moving the forms about, but it is not steerable except by laboriously changing sets of wheels. Even so, no diagonal movement is possible. Carriage height is adjusted by inflating or deflating its pneumatic tires.
U.S. Pat. No. 3,320,646 to Wilkins shows a pouring form for an arcuate concrete roof which form is rolled around in folded condition on a trailer vehicle and unfolded when it reaches the desired location. Shore jacks then attached to hold the outer form members in extended position and the vehicle has hydraulic jacks to vertically change the height of the form. However, the form is not a flying truss deck form and is not handled in the manner set forth and claimed in this disclosure, but is a modular device moved on the vehicle from one poured bay to the next adjacent one at the same level.